Liquid discharge apparatus

ABSTRACT

There is provided a liquid discharge apparatus including: a head including a nozzle surface on which a nozzle is opened; a carriage holding the head and configured to move in the scanning direction; a cap configured to contact the nozzle surface to cover the nozzle in a case that the carriage is located in a first position; and a contact member. The head includes a contact part configured to make contact with the contact member. In a case that a load of a vertical component of the nozzle surface is applied to the head by the cap contacting the nozzle surface, the contact member is configured to make contact with the contact part of the head to receive the load applied to the head.

REFERENCE TO RELATED APPLICATIONS

This application claims priority from Japanese Patent Application No.2022-116321, filed on Jul. 21, 2022. The entire content of the priorityapplication is incorporated herein by reference.

BACKGROUND ART

As an example of a liquid discharge apparatus configured to dischargeliquid from a nozzle, an image recording apparatus including aninkjet-type recording head (a head) is known. In a known image recordingapparatus, the recording head is mounted on a carriage. The carriage isslidably supported over a first guide member and a second guide memberextending in a main scanning direction and can move back and forth inthe main scanning direction. The recording head is mounted on thecarriage with the nozzle surface with nozzles facing downward. The firstguide member has a protrusion that fits into an engagement recess formedin the carriage. The engagement recess extends in a direction parallelto the nozzle surface.

In a known inkjet printer (a liquid discharge apparatus), a cap islocated within the travel range of the carriage carrying the inkjet head(a head). The cap can cover the nozzle by contacting the nozzle surfaceon the lower surface of the inkjet head. By covering the nozzle with thecap, the drying of ink in the nozzle can be suppressed.

DESCRIPTION

When the nozzle is covered with the cap, a load from the cap is appliedto the head in a direction orthogonal to the nozzle surface. In theabove-known image recording apparatus, the carriage contacts the firstguide member (a contact member) when a load is applied to the recordinghead (a head) in a direction orthogonal to the nozzle surface. Moreprecisely, the wall surface defining the engagement recess in thecarriage contacts the protrusion extending in a direction parallel tothe nozzle surface formed in the first guide member. Therefore, the loadapplied to the head is received by the contact member via the carriage.

When the load applied to the head is received by the contact member viathe carriage, stress is applied to the contact part of the carriage withthe contact member and a fastening part with the head. If the carriageis irreversibly deformed by the stress, the position of the nozzlesurface of the head mounted on the carriage may shift from thepredetermined position. When the position of the nozzle surface changes,the size of the gap between the nozzle surface and the recording mediumchanges. As a result, the accuracy of image formation on the recordingmedium is reduced. Also, if the position of the nozzle surface changes,the reliability of the contact between the nozzle surface and the capwill decrease.

The purpose of the present disclosure is to provide a technique thatcontributes to suppressing the misalignment of the nozzle surface of aliquid discharge apparatus.

According to an aspect of the present disclosure, there is provided aliquid discharge apparatus including a head, a carriage, a cap and acontact member. The head includes a nozzle surface on which a nozzle isopened. The carriage holds the head and is configured to move in thescanning direction. The cap is configured to contact the nozzle surfaceto cover the nozzle in a case that the carriage is located in a firstposition. The head includes a contact part configured to make contactwith the contact member. In a case that a load of a vertical componentof the nozzle surface is applied to the head by the cap contacting thenozzle surface, the contact member is configured to make contact withthe contact part of the head to receive the load applied to the head.

According to another aspect of the present disclosure, there is provideda liquid discharge apparatus including a head, a guide member, and acarriage. The head includes a nozzle surface on which a nozzle isopened. The guide member extends to a scanning direction. The carriageholds the head in a removable manner and is configured to move in thescanning direction while being guided by the guide member. The head isconfigured to make contact with the guide member, is located upstream ofthe guide member in a removal direction from the carriage and includes acontact part configured to face the guide member in the removaldirection. The guide member includes a cutout. The contact part faces aportion in the guide member where the cutout is not formed in a casethat the carriage is located in a first position and faces the cutout ina case that the carriage is located in a second position different fromthe first position in the scanning direction. In a case that a load of avertical component of the nozzle surface is applied to the head and thatthe carriage is located in the first position, the guide member isconfigured to make contact with the contact part of the head to receivethe load applied to the head.

According to the liquid discharge apparatus as described above, when thecarriage is in the first position, the contact part of the head is incontact with the contact member, and the load applied to the head can bereceived by the contact member without the carriage. Therefore,deformation of the carriage can be prevented, and misalignment of thenozzle surface of the head mounted on the carriage can be suppressed.

FIG. 1 is a schematic diagram of the printer.

FIG. 2 is a block diagram depicting the electrical configuration of theprinter.

FIG. 3 depicts a cross-sectional view of the recording head unit withthe nozzle surface capped and the guide rail and the carriage in a planeperpendicular to the scanning direction.

FIG. 4 is a diagonal downward view of the carriage.

FIGS. 5A and 5B are oblique downward views of the carriage, FIG. 5Adepicting the unit insertion position and FIG. 5B depicting the carriageinsertion position.

FIGS. 6A and 6B depict the procedure for mounting the recording headunit to the carriage. FIG. 6A depicts the state before the recordinghead unit is fitted and FIG. 6B depicts the state after the front end ofthe recording head unit is fitted.

FIGS. 7A and 7B depict the procedure for mounting the recording headunit to the carriage. FIG. 7A depicts the state after the recording headunit is fitted and FIG. 7B depicts the state after the mounting iscompleted.

FIG. 8 depicts the printer.

A printer 1 (corresponding to the “liquid discharge apparatus” of thepresent disclosure) will be described below with reference to thedrawings.

<Overall Configuration of Printer 1>

First, the overall configuration of the printer 1 is described withreference to FIGS. 1 and 2 . As depicted in FIG. 1 , the printer 1 ismainly equipped with guide rails 2, 3, a carriage 4, a tube joint 5, arecording head unit 6, a paper feed roller 11, a paper discharge roller12, a cap 13, a suction pump 14, a controller 17, and a housing 9.

The guide rails 2, 3 are made of sheet-metal materials and extend alongthe scanning direction. The scanning direction is horizontal andorthogonal to the front-rear direction. The two guide rails 2, 3 areapart from each other in the front-rear direction. The guide rail 2 islocated more rearward than the guide rail 3. The vicinity of both endsof the guide rails 2, 3 in the scanning direction are supported by apair of side frames 15 a, 15 b. The side frames 15 a, 15 b are attachedto the housing 9. In other words, the guide rails 2, 3 are supportedagainst housing 9 via the side frames 15 a, 15 b. The platen 10 islocated below the two guide rails 2, 3. The platen 10, of which uppersurface the recording paper P (recording medium) is placed, is locatedbetween the pair of side frames 15 a, 15 b.

The carriage 4 is mounted on the two guide rails 2, 3. The carriage 4 issupported from below by the two guide rails 2, 3. The carriage 4 canmove in the scanning direction while being guided by the two guide rails2, 3. The carriage 4 is attached to an unterminated drive belt (notdepicted) that is wound around a pair of pulleys (not depicted). Thedrive belt runs when the pulleys are driven to rotate by the carriagedrive motor 95 (see FIG. 2 ), which causes the carriage 4 to move backand forth in the scanning direction.

Tube joint 5 is attached to the carriage 4. The ends of the supply tubes92 connected to each of the four ink cartridges 91 are connected to thetube joint 5. The four ink cartridges 91 are mounted in the cartridgemounting section 90 provided at the front end in the housing 9. The fourink cartridges 91 corresponding to four colors (black, yellow, cyan, andmagenta) are mounted in the cartridge mounting section 90. The fourcolors of ink from each of the four ink cartridges 91 are supplied tothe tube joint 5 via the supply tubes 92.

The recording head unit 6 is held on the carriage 4 in a removablemanner. As will be described in detail later, the recording head unit 6has a sub-tank 7 that can be connected to the tube joint 5, an inkjethead 8, and a case 61 that houses the sub-tanks 7 and the inkjet head 8(see FIG. 3 ). The sub-tank 7 is connected to the tube joint 5. As aresult, four colors of ink from the four ink cartridges 91 are suppliedto each of the four intra-head flow channels 28 (see FIG. 3 ) of theinkjet head 8 via the tube joint 5 and the sub-tank 7.

The nozzle surface 20Y (see FIG. 3 ), which is the lower surface of theinkjet head 8, has a plurality of nozzles 22 (see FIG. 1 ) openings. Thenozzle surface 20Y is a horizontal plane. When a driver IC 98 (see FIG.2 ) is driven, the ink supplied to the intra-head flow channel 28 of theinkjet head 8 is ejected from the plurality of nozzles 22.

The paper feed roller 11 and the paper discharge roller 12 are driven bya conveying motor 96 (see FIG. 2 ), which rotates synchronously witheach other. The paper feed roller 11 and the paper discharge roller 12work together to convey the recording paper P placed on the platen 10.The conveyance direction of the recording paper P by the paper feedroller 11 and the paper discharge roller 12 is horizontal and orthogonalto the scanning direction and is from backward to forward. The paperfeed roller 11 and the paper discharge roller 12 correspond to the“conveyor” of the present disclosure.

The cap 13 is located on one side of the scanning direction than theside frame 15 b, which is located on one side of the scanning directionamong the pair of side frames 15 a, 15 b. The cap 13 faces the nozzlesurface 20Y of the inkjet head 8 in the up-down direction when thecarriage 4 is moved to the standby position (corresponding to the “firstposition” in the present disclosure) on one side of the scanningdirection than the side frame 15 b. The cap 13 is driven by theelevation motor 97 (see FIG. 2 ) and can be raised and lowered in theup-down direction. The cap 13 can take a capping position (the positiondepicted in FIG. 3 ), which is in contact with the nozzle surface 20Y ofthe inkjet head 8, and an uncapped position, which is lower than thecapping position and separated from the nozzle surface 20Y. The cap 13is formed primarily of an elastic material such as rubber. The cap 13consists of a flat floor portion and an annular lip portion located onthe outer edge of the floor portion. With the carriage 4 in the standbyposition, when the cap 13 is raised from the detached position to thecapping position by the elevation motor 97, the upper-end of the lipportion of the cap 13 is in close contact with the nozzle surface 20Y.As a result, the plurality of nozzles 22 are covered by the cap 13. Inthe printer 1, when the printer is in standby mode without printing, thecarriage 4 is in the standby position and the plurality of nozzles 22are covered by the cap 13. This prevents the ink in the nozzles 22 fromdrying.

The suction pump 14 is a tube pump or similar device and is connected tothe cap 13 and the waste tank 21. The suction pump 14 can be drivenwhile the multiple nozzles 22 are covered by the cap 13. This allows aso-called suction purge to be performed. In the suction purge, the inkdischarged by the suction purge, in which the ink in the inkjet head 8and air, etc. mixed in the sub-tank 7 are discharged from the pluralityof nozzles 22, is transferred to the waste liquid tank 21.

As depicted in FIG. 2 , the controller 17 includes a CPU 81 (CentralProcessing Unit), an ASIC 82 (Application Specific Integrated Circuit)and a memory 83. The CPU 81, ASIC 82 and memory 83 are connected by aninternal bus. The memory 83 is connected by an internal bus. The memory83 includes ROM 83 a (Read Only Memory), RAM 83 b (Random AccessMemory), and EEPROM 83 c (Electrically Erasable Programmable Read-OnlyMemory), CPU 81 executes the program while using RAM 83 b and EEPROM 83c. The ASIC 82 is electrically connected to the driver IC 98 of theinkjet head 8, the carriage driving motor 95, the conveying motor 96,the elevation motor 97, and the suction pump 14. The ASIC 82 outputscontrol signals to the driver IC 98, the carriage driving motor 95, theconveying motor 96, the elevation motor 97, and the suction pump 14 tocontrol their operation.

The controller 17 controls the driver IC 98, the carriage driving motor95, and the conveying motor 96 based on the recording data transmittedfrom an external device (e.g., PC or smartphone). As a result, thecontroller 17 causes the inkjet head 8 to alternately perform theconveyance operation and the recording operation to record an image onthe recording paper P. Specifically, in the conveyance operation, thecontroller 17 controls the conveying motor 96 to convey the recordingpaper P by the paper feed roller 11 and the paper discharge roller 12 inthe conveyance direction. In the recording operation, the controller 17controls the driver IC 98 and the carriage driving motor 95 to eject inkfrom nozzle 22 while moving the inkjet head 8 together with the carriage4 in the scanning direction.

The range A depicted in FIG. 1 is the range of movement of the carriage4 with respect to the scanning direction in the recording operation. Thecarriage 4 moves from one side of the platen 10 to the other side withrespect to the scanning direction in the recording operation. The rangeB depicted in FIG. 1 is the facing range where the nozzle surface 20Yfaces the platen 10. More precisely, when the carriage 4 is positionedwithin the range B, at least a part of the nozzle surface 20Y faces theplaten 10. The range A includes the entirety of the range B. In therecording operation, the controller 17 moves the carriage 4 back andforth in range A and causes ink to be ejected from the nozzles 22 of theinkjet head 8 when the carriage 4 passes through the range B inside therange A.

The configuration of the guide rails 2, 3, the carriage 4, the tubejoint 5, and the recording head unit 6 will then be explained withfurther reference to FIGS. 3 to 5 .

<Composition of Guide Rails 2, 3>

As depicted in FIG. 3 , the guide rail 2, which is made of sheet-metalmaterial, has its thickness direction roughly parallel to the up-downdirection. Both ends of the guide rail 2 in the front-rear direction areprovided with curved portions 2 a and 2 b, which are bent upward. Theupper-end of the curved portion 2 b at the forward end of the guide rail2 is bent forward. In other words, the curved portion 2 b includes aportion extending in the up-down direction and a portion extending inthe front-rear direction. Similarly, the guide rail 3, which is made ofsheet-metal material, has its thickness direction roughly parallel tothe up-down direction. Both ends of the guide rail 3 in the front-reardirection are provided with curved portions 3 a and 3 b which are bentupward.

As depicted in FIG. 1 , cutouts 16 a and 16 b are formed near the otherend of the guide rail 2 in the scanning direction. The cutouts 16 a and16 b are formed in the curved portion 2 b of the guide rail 2 thatextends in the front-rear direction. The front side of the cutouts 16 aand 16 b is open. The separation distance between the two cutouts 16 aand 16 b with respect to the scanning direction is distance D1.

The cutouts 16 a, 16 b are located on the outside of the pair of sideframes 15 a, 15 b. In detail, the cutouts 16 a, 16 b are located on theother side of the scanning direction than the side frame 15 a, which islocated on the other side of the scanning direction among the pair ofside frames 15 a, 15 b. The cutouts 16 a and 16 b are located outsidethe range A, which is the range of movement of the carriage 4 withrespect to the scanning direction in the recording operation. In otherwords, the location of the cutouts 16 a and 16 b is also outside therange B, which is the facing range where at least a part of the nozzlesurface 20Y faces the platen 10. More precisely, the cutouts 16 a and 16b are located on the other side than the other end of the scanningdirection in the range A.

<Configuration of Carriage 4>

As depicted in FIG. 3 , a groove 41 is formed at the rear end of thecarriage 4, wherein the groove 41 is opened downward and extends alongthe scanning direction. The curved portion 2 b of the guide rail 2 isfitted into the groove 41. In addition, a groove 42, which is openeddownward and extends along the scanning direction, is formed in theforward portion of the carriage 4 from the portion where the groove 41is formed. The curved portion 3 a provided at the rear end of the guiderail 3 is fitted into the groove 42.

An opening 47 penetrating in the up-down direction is formed between theportion of the carriage 4 where groove 41 is formed and the portionwhere groove 42 is formed in the front-rear direction. In other words,the opening 47 of the carriage 4 is located between the two guide rails2, 3 with respect to the front-rear direction. The recording head unit 6is fitted into the opening 47. A direction of removal (a removaldirection), from the carriage 4, of the recording head unit 6 fittedinto the opening 47 is from downward to upward.

The forward end of the carriage 4 is an overlap portion 43, whichoverlaps the guide rail 3 in the up-down direction. The overlap portion43 is located above the guide rail 3. The overlap portion 43 has anupwardly facing and horizontally extending surface 43 a. The tube joint5 is attached to the surface 43 a of the overlap portion 43 in thecarriage 4.

A lever 44 is provided at the forward end of the overlap portion 43 ofthe carriage 4. The lever 44 has a first member 45 and a second member46. The first member 45 is rotatable about a shaft 45 a extending alonga direction parallel to the scanning direction. The shaft 45 a of thefirst member 45 is attached to the overlap portion 43. The first member45 extends along a direction of extension parallel to a plane orthogonalto the scanning direction (hereinafter referred to as the “orthogonalplane”), with the portion where the shaft 45 a is provided as one-endportion. The second member 46 is rotatable around a shaft 46 a extendingalong a direction parallel to the scanning direction. The shaft 46 a ofthe second member 46 is attached to the other end of the first member 45opposite to the one-end where the shaft 45 a is provided in the firstmember 45 with respect to the direction of extension of the first member45 that extends parallel to the orthogonal plane. The second member 46extends along the direction of extension parallel to the orthogonalplane, with the shaft 46 a being provided at one-end.

The second member 46 is provided with an engaging part 46 b. Theengaging part 46 b is provided near the other end of the second member46 opposite to the one-end where the shaft 46 a is provided, withrespect to the extension direction of the second member 46 extending ina direction parallel to the orthogonal plane. The engaging part 46 b canengage an opening 61 a provided in the case 61 of the recording headunit 6. The opening 61 a penetrates in the up-down direction. Theopening 61 a is located above the overlap portion 43 of the carriage 4and opposite the rear end of the overlap portion 43 vertically.

The lever 44 can take a first position (see FIG. 2 and FIG. 7B) and asecond position (see FIGS. 6A, 6B and 7A) by being operated by the user.When the lever 44 is in the first position, the extension of the firstmember 45 in the orthogonal plane orthogonal to the scanning directionis in the up-down direction and the extension of the second member 46 isin the front-rear direction. When the lever 44 is in the first position,the second member 46 is above the overlap portion 43 of the carriage 4and is vertically opposite to the overlap portion 43. When the lever 44is in the first position, the engaging part 46 b on the second member 46of the lever 44 protrudes downwardly from the lower surface of thesecond member 46. When the lever 44 is in the first position, theengaging part 46 b engages the opening 61 a in the case 61 of therecording head unit 6 that is fitted into the opening 47 of the carriage4.

When the vicinity of the engaging part 46 b in the lever 44 in the firstposition is lifted upward by the user, the opening 61 a and the engagingpart 46 b are disengaged. When the lever 44 is further pulled forward bythe user, the lever 44 is positioned in the second position (see FIGS.6A, 6B and 7A). When the lever 44 is in the second position, the otherend of the first member 45 in the extending direction is located moreforward than the one-end in the extending direction (the part attachedto the overlap portion 43). The extending direction is parallel to theorthogonal plane orthogonal to the scanning direction. The shaft 46 a ofthe second member 46 is attached to the other end of the first member 45in the extending direction. One-end of the first member 45 in theextending direction is attached to the overlap portion 43. When theposition of the lever 44 changes between the first and second positions,the first member 45 moves between an upright position and an obliqueposition. In the upright position, the extension of the first member 45in the orthogonal plane is in the up-down direction. In the obliqueposition, the other end of the first member 45 in the extendingdirection is more forward than the one-end in the extending direction.

The tube joint 5 attached to the overlap portion 43 of the carriage 4slides in the front-rear direction in conjunction with the first member45 of the lever 44 moving between the upright and oblique positions bymeans of an interlocking mechanism (not depicted). Specifically, whenthe first member 45 of the lever 44 moves from the oblique position tothe upright position, i.e., when the lever 44 moves from the secondposition to the first position, the tube joint 5 slides from forward tobackward. This allows the tube joint 5 to be connected to the sub-tank7. When the first member 45 of the lever 44 moves from the uprightposition to the oblique position, i.e., when the lever 44 moves from thefirst position to the second position, the tube joint 5 slides frombackward to forward. This allows the connection between the tube joint 5and the sub-tank 7 to be disconnected.

The carriage 4 is provided with claw portions 48 a, 48 b and a hookportion 49 to prevent the carriage 4 from exiting the guide rails 2, 3,as depicted in FIG. 4 . The claw portions 48 a, 48 b and a curvedportion 49 a described below of the hook portion 49 correspond to the“carriage-side facing portion” of the present disclosure.

The claw portions 48 a, 48 b protrude rearwardly from the rear lateralwall in the carriage 4. The claw portions 48 a, 48 b are located apartin the scanning direction. The claw portions 48 a, 48 b are locatedbelow the curved portion 2 b of the guide rail 2 (upstream of theremoval direction). The claw portions 48 a, 48 b face the curved portion2 b of the guide rail 2 with respect to the up-down direction (removaldirection).

The hook 49 protrudes downward from the lower lateral wall of thecarriage 4 and has its lower-end bent forward as a curved portion 49 a.The curved portion 49 a of the hook 49 is located on the lower side ofthe guide rail 3 (upstream of the removal direction). The curved portion49 a of the hook 49 faces the guide rail 3 in the up-down direction(removal direction).

The distance D2, which is the separation distance with respect to thescanning direction between the two claw portions 48 a, 48 b, isapproximately equal to the distance D1, which is the separation distancewith respect to the scanning direction between the two cutouts 16 a, 16b. Therefore, as depicted in FIG. 5B, the two claw portions 48 a and 48b on the carriage 4 can be located in the carriage removal positionopposite to areas where the two cutouts 16 a and 16 b are formed in theguide rail 2, respectively. When the carriage 4 is in the carriageremoval position, the claw portions 48 a, 48 b can pass through thecutouts 16 a, 16 b. Therefore, the claw portions 48 a, 48 b can bepulled out from below the guide rail 2 to above the guide rail 2 throughthe cutouts 16 a, 16 b. When the carriage 4 is in the carriage removalposition, the hook 49 is located on the other side of the guide rail 3than the other end in the scanning direction. In other words, at thistime, the curved portion 49 a of the hook 49 does not face the guiderail 3 with respect to the up-down direction. Therefore, the carriage 4can be pulled upwardly from the guide rails 2, 3 when the carriage 4 isin the carriage removal position.

When the carriage 4 is not in the carriage removal position, the clawportions 48 a and 48 b contact the curved portions 2 b of the guide rail2 and the curved portion 49 a of the hook portion 49 contacts the guiderail 3 when the carriage 4 is lifted upward. This prevents the carriage4 from exiting the guide rails 2, 3.

<Composition of Tube Joint 5>

As depicted in FIG. 3 , the tube joint 5 has a portion extending alongthe up-down direction and a portion extending rearward from thelower-end of the portion extending along the up-down direction. The tubejoint 5 is attached to the carriage 4 so that the lower surface of theportion extending along the front-rear direction faces the surface 43 aof the overlap portion 43.

A cartridge-side connecting portion 51 a is provided on the wall on oneside of the scanning direction in the portion of the tube joint 5 thatextends along the up-down direction. The cartridge-side connectingportion 51 a is connected to the end of the supply tube 92 connected tothe ink cartridge 91. Four cartridge-side connecting portions 51 a areprovided in a row along the up-down direction. The four cartridge-sideconnecting portions 51 a correspond to four colors: black, yellow, cyan,and magenta.

A head-side connecting portion 52 a is provided on the rear lateral wallof the portion of the tube joint 5 that extends along the front-reardirection. The head-side connecting portion 52 a is connected to thesub-tank 7 which constitutes the recording head unit 6. Four head-sideconnecting portions 52 a are provided in a row along the scanningdirection. The four head-side connecting portions 52 a correspond to thefour colors: black, yellow, cyan, and magenta.

Four ink channels (not depicted) are formed in the tube joint 5. The inkis supplied to the four ink channels from the supply tubes 92 connectedto the four cartridge-side connecting portions 51 a, respectively. Theink in the ink channels of the tube joint 5 is then supplied to the inkchannels (not depicted) formed in the sub-tank 7 connected to thehead-side connecting portion 52 a.

<Configuration of Recording Head Unit 6>

The configuration of the recording head unit 6 is described next. Asdepicted in FIG. 3 , the recording head unit 6 has the sub-tank 7, theinkjet head 8, and the case 61 that houses the sub-tanks 7 and theinkjet head 8.

As depicted in FIG. 3 , the sub-tank 7 has a portion extending along thefront-rear direction and a portion extending downward from the rear endof the portion extending along the front-rear direction. The frontlateral wall of the portion extending along the front-rear direction ofthe sub-tank 7 is provided with four connecting portions 71 a. The fourconnecting portions 71 a are aligned along the scanning direction. Arubber connecting member 85 is attached to the connecting portions 71 a.The four connecting portions 71 a are connected to the four head-sideconnecting portions 52 a on the tube joint 5 respectively via theconnecting member 85.

Four ink channels (not depicted) are formed in the sub-tank 7. Ink issupplied to the four ink channels respectively from the four inkchannels (not depicted) formed in the tube joint 5, which is connectedto the sub-tank 7 via the connecting member 85.

The lower-end of the portion extending along the up-down direction inthe sub-tank 7 is located on the upper surface of the inkjet head 8. Thefour ink channels formed in the sub-tank 7 are each opening at thelower-end of the portion extending along the up-down direction in thesub-tank 7. Ink in the four ink channels of the sub-tank 7 is suppliedto each of the four intra-head flow channels 28 formed in the inkjethead 8 via ink supply ports 28 a formed on the upper surface of theinkjet head 8.

Four intra-head flow channels 28 are formed in the inkjet head 8, eachcontaining a plurality of nozzles 22 (see FIG. 1 ). The lower surface ofthe inkjet head 8 is the nozzle surface 20Y, on which the plurality ofnozzles 22 is formed. On the upper surface of the inkjet head 8, thefour ink supply ports 28 a are formed to supply ink to each of the fourintra-head flow channels 28. As described above, the four ink supplyports 28 a are connected to the ends of the four ink channels formed inthe sub-tank 7, respectively.

When the head-side connecting portion 52 a in the tube joint 5 isconnected to the connecting portion 71 a in the sub-tank 7, the inksupplied from the ink cartridge 91 via the supply tube 92 to the inkchannel (not depicted) in the tube joint 5 is sent to the ink channelformed in the sub-tank 7 (not depicted) to the intra-head flow channel28 of the inkjet head 8.

As depicted in FIG. 3 , the recording head unit 6 include the sub-tank 7and inkjet head 8 in the case 61 with the inkjet head 8 located belowthe sub-tank 7.

The case 61 has four claw portions 62 a, 62 b, 63 a, 63 b, as depictedin FIGS. 3 and 4 . The claw portions 62 a and 62 b can contact the guiderail 2. The claw portions 63 a and 63 b can contact the guide rail 3.The claw portions 62 a, 62 b, 63 a, 63 b correspond to the “contactpart” of the present disclosure.

The claw portions 62 a and 62 b protrude rearwardly from the rearsidewall of the case 61. The two claw portions 62 a and 62 b areseparated from each other in the scanning direction. The claw portions62 a and 62 b are located below the curved portion 2 b of the guide rail2 (upstream of the removal direction). The claw portions 62 a and 62 bare opposite the curved portions 2 b of the guide rail 2 with respect tothe up-down direction (in the removal direction).

The claw portions 63 a, 63 b protrude forward from the front lateralwall of the case 61. The two claw portions 63 a, 63 b are separated fromeach other in the scanning direction. The claw portions 63 a and 63 bare located on the lower side of the guide rail 3 (upstream of theremoval direction). The claw portions 63 a and 63 b face the guide rail3 with respect to the up-down direction (in the removal direction).

The distance D3, which is the separation distance between the two clawportions 62 a, 62 b with respect to the scanning direction, isapproximately equal to the distance D1, which is the separation distancebetween the two cutouts 16 a, 16 b with respect to the scanningdirection. Therefore, as depicted in FIG. 5 a , the carriage 4 can belocated in the unit removal position (corresponding to the “secondposition” of the present disclosure) where the two claw portions 62 aand 62 b on the case 61 of the recording head unit 6 face the locationswhere the two cutouts 16 a and 16 b are formed in the guide rail 2,respectively. When the carriage 4 is in the unit removal position, theclaw portions 62 a and 62 b can pass through the cutouts 16 a and 16 b.Therefore, the claw portions 62 a, 62 b can be pulled out from below theguide rail 2 to above the guide rail 2 through the cutouts 16 a, 16 b.

When the carriage 4 is not in the unit removal position, the clawportions 62 a and 62 b face the curved portions 2 b of guide rail 2 andthe claw portions 63 a, 63 b face the guide rail 3. Therefore, when thecarriage 4 is in the standby position facing the cap 13, the cap 13contacts the nozzle surface 20Y. As a result, when a load of thevertical component (upward component) of the nozzle surface 20Y isapplied to the recording head unit 6, the claw portions 62 a and 62 bcontact the curved portion 2 b of the guide rail 2, and the clawportions 63 a and 63 b contact the guide rail 3. At this time, the guiderails 2, 3 are in contact with the claw portions 62 a, 62 b, 63 a, 63 band receive the load applied to the recording head unit 6.

Of the pair of claw portions 62 a and 62 b, the claw portion 62 alocated on one side of the scanning direction is located on the otherside of the scanning direction than the claw portion 48 a located on oneside of the scanning direction of the pair of claw portions 48 a and 48b formed on the carriage 4. The claw portion 62 b, which is located onthe other side of the scanning direction among the pair of claw portions62 a, 62 b, is located on the other side of the scanning direction thanthe claw portion 48 b, which is located on the other side of thescanning direction among the pair of claw portions 48 a, 48 b formed onthe carriage 4. The claw portions 63 a and 63 b are located on one sideof the scanning direction than the hook section 49 formed on thecarriage 4.

As depicted in FIG. 4 , the center position with respect to the scanningdirection in the recording head unit 6 is position C. At this time, theclaw portion 48 a is located on the opposite side of position C fromclaw portion 62 a with respect to the scanning direction. The clawportion 48 b is located between the claw portion 62 b and the position Cin the scanning direction.

<Mounting Procedure for Recording Head Unit 6>

Next, with further reference to FIGS. 6 and 7 , the procedure forattaching the recording head unit 6 to the carriage 4 is explained.

First, as depicted in FIG. 6A, the recording head unit 6 is fitted intothe opening 47 of the carriage 4 in the unit removal position from abovedownward. The recording head unit 6 is tilted so that the rear end ofthe nozzle surface 20Y is higher than the front end. At this time, thelever 44 of the carriage 4 is in the second position.

As depicted in FIG. 6B, after fitting the recording head unit 6 untilthe claw portions 63 a and 63 b formed on the front lateral wall in thecase 61 of the recording head unit 6 are below the guide rail 3, therecording head unit 6 is placed in a position where the nozzle surface20Y is horizontal, as depicted in FIG. 7A. At this time, the clawportions 62 a and 62 b formed on the rear lateral wall in the case 61 ofthe recording head unit 6 enter the curved portion 2 b of the guide rail2 from above and below through the cutouts 16 a and 16 b formed in thecurved portion 2 b of the guide rail 2.

As depicted in FIG. 7A, when the recording head unit 6 is fitted intothe opening 47 of the carriage 4, the connecting portion 71 a of thesub-tank 7 to which the connecting member 85 is attached is located onthe face 43 a of the overlap portion 43 of the carriage 4. At this time,the connecting portion 71 a of the sub-tank 7 faces the four head-sideconnecting portions 52 a of the tube joint 5, respectively, with respectto the front-rear direction. The connecting portions 71 a of thesub-tank 7 are located rearwardly of the head-side connecting portions52 a of the tube joint 5.

Then, as depicted in FIG. 7B, the lever 44 is moved from the secondposition to the first position, and the engaging part 46 b of the lever44 is engaged with the opening 61 a in the case 61 of the recording headunit 6. At this time, the tube joint 5 slides from the front side to therear side as the lever 44 moves from the second position to the firstposition. As a result, the four head-side connecting portions 52 a ofthe tube joint 5 and the four connecting portions 71 a of the sub-tank 7are connected respectively via the connecting member 85. In other words,the tube joint 5 and the sub-tank 7 are connected via the connectingmember 85.

To remove the recording head unit 6 from the carriage 4, the carriage 4is located in the unit removal position. Then, the opening 61 a in thecase 61 of the recording head unit 6 and the engaging part 46 b of thelever 44 are disengaged, and the lever 44 is moved from the firstposition to the second position. As the lever 44 moves from the firstposition to the second position, the tube joint 5 slides from the rearside to the front side. This allows the connection between the tubejoint 5 and the sub-tank 7 to be disconnected.

The recording head unit 6 is then tilted so that the rear end of thenozzle surface 20Y is higher than the front end. At this time, the clawportions 62 a and 62 b are pulled out from below the guide rail 2 toabove the guide rail 2 through the cutouts 16 a and 16 b. The recordinghead unit 6 is then lifted upward from below and pulled out from theopening 47 of the carriage 4. At this time, as depicted in FIG. 5A, theclaw portions 48 a, 48 b and the hook 49 formed on the carriage 4 arepositioned opposite the guide rails 2, 3. Therefore, the claw portions48 a, 48 b and the hook 49 are in contact with the guide rails 2, 3 toprevent the carriage 4 from coming off the guide rails 2, 3 togetherwith the recording head unit 6.

<Technical Features of the Embodiment>

As described above, the printer 1 includes the carriage 4 configured tomove back and forth in the scanning direction, and the cap 13 that cancover the nozzle 22 in contact with the nozzle surface 20Y of therecording head unit 6 mounted on the carriage 4 when the carriage 4 isin the standby position. The recording head unit 6 includes the clawportions 62 a, 62 b, 63 a, 63 b that can contact the guide rails 2, 3.When a load of the vertical component of the nozzle surface 20Y isapplied to the recording head unit 6 by the cap 13 contacting the nozzlesurface 20Y, the guide rails 2, 3 contact the claw portions 62 a, 62 b,63 a, 63 b of the recording head unit 6 to receive the load applied tothe recording head unit 6.

The above configuration allows the claw portions 62 a, 62 b, 63 a, 63 bof the recording head unit 6 to contact the guide rails 2, 3 when thecarriage 4 is in the standby position, and the load applied to therecording head unit 6 is received by the guide rails 2, 3 without thecarriage 4. Therefore, deformation of the carriage 4 can be preventedand misalignment of the nozzle surface 20Y of the recording head unit 6mounted on the carriage 4 can be suppressed.

In the printer 1 of the embodiment described above, the carriage 4 holdsthe recording head unit 6 in a removable manner. The claw portions 62 a,62 b, 63 a, 63 b of the recording head unit 6 are located upstream ofthe guide rails 2, 3 with respect to the removal direction of therecording head unit 6 from the carriage 4 and can face the guide rails2, 3 with respect to the removal direction. The cutouts 16 a and 16 bare formed in the guide rail 2, which are opposite the claw portions 62a and 62 b of the recording head unit 6 with respect to the removaldirection when the carriage 4 is in the unit removal position, which isdifferent from the standby position with respect to the scanningdirection. Therefore, when the carriage 4 is in the unit removalposition, the claw portions 62 a and 62 b of the recording head unit 6can pass through the cutouts 16 a and 16 b of the guide rail 2. Thus,the recording head unit 6 can be attached to and detached from thecarriage 4. Also, for example, the rigidity of the guide rail 2 can beincreased compared to the case where the cutouts that allow the clawportions 62 a, 62 b to pass through are formed throughout the guide rail2, including the locations facing the claw portions 62 a, 62 b of therecording head unit 6 when the carriage 4 is in the standby position.

In addition, in the printer 1 of the embodiment described above, theload applied to the recording head unit 6 can be received by the guiderails 2, 3, which are members that guide the carriage 4.

Furthermore, in the printer 1 of the embodiment described above, thecutouts 16 a, 16 b of the guide rail 2 are located outside the range B,which is the facing range where at least a part of the nozzle surface20Y faces the platen 10. When the carriage 4 moving while being guidedby the guide rails 2, 3 passes through the portion of the guide rail 2where the cutouts 16 a and 16 b are formed, the recording head unit 6may tilt. In this configuration, the carriage 4 does not pass throughthe portion where the cutouts 16 a and 16 b are formed when the carriage4 is moving within the range B where at least part of the nozzle surface20Y faces the platen 10 while being guided by the guide rails 2, 3.Therefore, the recording head unit 6 can be suppressed from tilting anddisrupting the formed image when ink is being discharged onto therecording paper P supported by the platen 10.

In the printer 1 of the embodiment described above, the cutouts 16 a and16 b of the guide rail 2 are located outside the range A, which is therange of movement of the carriage 4 in the scanning direction in therecording operation. Therefore, when the carriage 4 is moving within therange A while being guided by the guide rails 2, 3 during the recordingoperation, it does not pass through the portion where the cutouts 16 aand 16 b are formed. Therefore, it is possible to suppress the tiltingof the recording head unit 6 during the recording operation, whichdisturbs the formed image.

Furthermore, the printer 1 in the embodiment described above has a pairof side frames 15 a, 15 b that support the guide rails 2, 3 near bothends in the scanning direction, respectively. The cutouts 16 a, 16 b ofthe guide rail 2 are located outside of the pair of side frames 15 a, 15b with respect to the scanning direction. Therefore, the strength of theguide rail 2 can be reduced compared to the case where the cutouts 16 a,16 b are located inside the pair of side frames 15 a, 15 b with respectto the scanning direction.

In addition, the printer 1 of the embodiment described above has thecarriage 4 located upstream of the guide rails 2, 3 with respect to theremoval direction, and has claw portions 48 a, 48 b and hook portion 49facing the guide rails 2, 3 with respect to the removal direction whenthe carriage 4 is in the unit removal position. Therefore, when therecording head unit 6 is removed from the carriage 4 and when thecarriage 4 is in the unit removal position, the claw portions 48 a, 48 band the hook portions 49 are in contact with the guide rails 2, 3 toprevent the carriage 4 from being removed from the guide rails 2, 3together with the recording head unit 6.

While the invention has been described in conjunction with variousexample structures outlined above and illustrated in the figures,various alternatives, modifications, variations, improvements, and/orsubstantial equivalents, whether known or that may be presentlyunforeseen, may become apparent to those having at least ordinary skillin the art. Accordingly, the example embodiments of the disclosure, asset forth above, are intended to be illustrative of the invention, andnot limiting the invention. Various changes may be made withoutdeparting from the spirit and scope of the disclosure. Therefore, thedisclosure is intended to embrace all known or later developedalternatives, modifications, variations, improvements, and/orsubstantial equivalents. Some specific examples of potentialalternatives, modifications, or variations in the described inventionare provided below.

The above embodiment describes a case in which the printer 1 is equippedwith a cap 13 that can cover the nozzle 22 in contact with the nozzlesurface 20Y. The present disclosure is not limited to such aconfiguration. The printer 1 may not be provided with the cap 13. Whenthe carriage 4 is in the first position, the claw portions 62 a and 62 bof the recording head unit 6 may face the portion of the guide rail 2 inwhich the cutouts 16 a and 16 b are not formed. Furthermore, when thecarriage 4 is in the second position, which is different from the firstposition with respect to the scanning direction, the claw portions 62 a,62 b of the recording head unit 6 may face the cutouts 16 a, 16 b in theguide rail 2. In this configuration, when the load of the verticalcomponent of the nozzle surface 20Y is applied to the recording headunit 6 when the carriage 4 is in the first position, the guide rail 2contacts the claw portions 62 a and 62 b of the recording head unit 6 toreceive the load applied to the recording head unit 6. Therefore,deformation of the carriage 4 can be reduced and misalignment of thenozzle surface 20Y of the recording head unit 6 mounted on the carriage4 can be suppressed. In addition, when the carriage 4 is in the firstposition, the recording head unit 6 cannot be attached to or detachedfrom the carriage 4, thus preventing user mishandling.

The above embodiment describes a case in which the claw portions 62 a,62 b, 63 a, 63 b formed on the recording head unit 6 are capable ofcontacting the guide rails 2, 3 that support the carriage 4 from below.However, the present disclosure is not limited to such a configuration.For example, in the printer 101 depicted in FIG. 8 , the carriage 104 issupported while being penetrated by the guide shaft 102 extending alongthe scanning direction. The carriage 104 can move back and forth in thescanning direction while being guided by the guide shaft 102. The guideshaft 102 supports the lower-end of the lateral wall 141 on the upstreamside in the conveyance direction in the carriage 104. A lock lever 144is attached to the lateral wall 141 of the carriage 104 to secure therecording head unit 106 mounted on the carriage 104.

A guide rail 103 extending along the scanning direction is locatedupstream of the carriage 104 in the transport direction. The guide rail103 is a plate-like member extending in the up-down direction, and itsupper-end is provided with a curved portion 103 a that is bentdownstream in the transport direction. The tip of the curved portion 103a contacts the upper-end portion of the downstream-facing surface 141 aof the lateral wall 141 of the carriage 4. The curved portion 103 asupports the surface 141 a of the lateral wall 141 in the carriage 4.This prevents the carriage 4 from rotating counterclockwise in FIG. 8around the guide shaft 102 due to gravity.

The lateral wall on the upstream side of the recording head unit 106 isprovided with a projection 162 protruding from the upstream side in theconveyance direction. The projection 162 projects from the downstreamside to the upstream side of the lateral wall 141 with respect to theconveyance direction through an opening 141 b formed in the lateral wall141 of the carriage 104. The tip of the projection 162 can contact theguide rail 103. In the printer 101, when a load of the verticalcomponent of the nozzle surface 20Y is applied to the recording headunit 106, the guide rail 103 contacts the projection 162 of therecording head unit 106 to receive the load applied to the recordinghead unit 106.

The members that the claw portions 62 a, 62 b, 63 a, 63 b formed on therecording head unit 6 come into contact with are not limited to membersfor guiding the carriage 4. For example, when a load is applied to therecording head unit 6, a member may be provided as a dedicated memberthat contacts a part of the recording head unit 6 and receives the loadapplied to the recording head unit 6.

In addition, the above embodiment describes a case in which therecording head unit 6 has two claw portions 62 a and 62 b that cancontact the guide rail 2 and two claw portions 63 a and 63 b that cancontact the guide rail 3. However, the present disclosure is not limitedto such a configuration. The recording head unit 6 need only be providedwith at least one contacting portion capable of contacting either theguide rail 2 or the guide rail 3.

Furthermore, the above embodiment describes a case in which cutouts 16 aand 16 b are formed in the guide rail 2 through which the claw portions62 a and 62 b of the recording head unit 6 can pass, but cutouts 16 aand 16 b may not be formed in the guide rail 2.

In the embodiment described above, the case is described where the unitremoval position is near the end of the other side of the guide rails 2,3 in the scanning direction. However, the present disclosure is notlimited to such a configuration. The unit removal position can be anyposition different from the standby position.

In addition, the above embodiment describes a case in which the cutouts16 a and 16 b of the guide rail 2 are located outside of the range A,the range of movement of the carriage 4 in the recording operation.However, the present disclosure is not limited to such a configuration.For example, the location of the cutouts 16 a and 16 b may be inside therange A and outside the range B, which is the facing range where atleast a part of the nozzle surface 20Y faces the platen 10. The locationof the cutouts 16 a and 16 b may be inside the range B.

In the embodiment described above, the cutouts 16 a and 16 b are locatedoutside of the pair of side frames 15 a, 15 b with respect to thescanning direction. However, the present disclosure is not limited tosuch a configuration. The cutouts 16 a, 16 b may be located inside thepair of side frames 15 a, 15 b.

In addition, the above embodiment describes a case in which the carriage4 is provided with the claw portions 48 a, 48 b and the hook 49 toprevent the carriage 4 from exiting the guide rails 2, 3. However, thepresent disclosure is not limited to such a configuration. These clawportions 48 a, 48 b and the hook 49 may be omitted.

Furthermore, the above embodiment describes a case in which therecording head unit 6 is removable from the carriage 4. However, thepresent disclosure is not limited to such a configuration. The recordinghead unit 6 may not be removable from the carriage 4.

This disclosure may be applied not only to printers equipped with headsthat eject ink, but also to devices equipped with heads that ejectliquids other than ink in general.

What is claimed is:
 1. A liquid discharge apparatus comprising: a headincluding a nozzle surface on which a nozzle is opened; a carriageholding the head and configured to move in the scanning direction; a capconfigured to contact the nozzle surface to cover the nozzle in a casethat the carriage is located in a first position; and a contact member,wherein the head includes a contact part configured to make contact withthe contact member, in a case that a load of a vertical component of thenozzle surface is applied to the head by the cap contacting the nozzlesurface, the contact member is configured to make contact with thecontact part of the head to receive the load applied to the head.
 2. Theliquid discharge apparatus according to claim 1, wherein the head isconfigured to be removable from the carriage in a removal direction, thecontact part of the head is located upstream of the contact member inthe removal direction, and is configured to face the contact member inthe removal direction, the contact member includes a cutout formed at aposition opposite to the contact part of the head in the removaldirection in a case that the carriage is located in a second positiondifferent from the first position in the scanning direction.
 3. Theliquid discharge apparatus according to claim 2, wherein the contactmember is a guide member extending in the scanning direction andconfigured to guide the carriage in the scanning direction.
 4. Theliquid discharge apparatus according to claim 3, wherein, the guidemember is a frame configured to support the carriage from below.
 5. Theliquid discharge apparatus according to claim 3, further comprising: aconveyor configured to convey a recording medium in a conveyancedirection; and a platen configured to support the recording mediumconveyed by the conveyor, wherein a travel range of the carriage in thescanning direction includes a facing range in which at least a part ofthe nozzle surface faces the platen, and the cutout is located outsideof the facing range in the scanning direction.
 6. The liquid dischargeapparatus according to claim 3, further comprising a controllerconfigured to execute a recording operation in which a liquid is ejectedfrom the nozzle toward the recording medium while the carriage isreciprocated within a travel range in the scanning direction, whereinthe cutout is located outside of the travel range in the scanningdirection.
 7. The liquid discharge apparatus according to claim 4,further comprising a pair of side frames configured to support both endsof the frame in the scanning direction, respectively, wherein the cutoutis located outside of the pair of side frames in the scanning direction.8. The liquid discharge apparatus according to claim 4, wherein thecarriage is located upstream from the frame in the removal direction andincludes a carriage-side facing portion configured to face the frame inthe removal direction in a case that the carriage is located in thesecond position.
 9. The liquid discharge apparatus according to claim 8,wherein the carriage-side facing portion is located, in the scanningdirection, between the contact part and a center position of the head inthe scanning direction.
 10. The liquid discharge apparatus according toclaim 8, wherein the carriage-side facing portion is located, in thescanning direction, opposite a center position of the head in thescanning direction across the contact part of the head.
 11. A liquiddischarge apparatus comprising: a head including a nozzle surface onwhich a nozzle is opened; a guide member extending to a scanningdirection; and a carriage holding the head in a removable manner andconfigured to move in the scanning direction while being guided by theguide member, wherein the head is configured to make contact with theguide member, is located upstream of the guide member in a removaldirection from the carriage, and includes a contact part configured toface the guide member in the removal direction, the guide memberincludes a cutout, the contact part faces a portion in the guide memberwhere the cutout is not formed in a case that the carriage is located ina first position, and faces the cutout in a case that the carriage islocated in a second position different from the first position in thescanning direction, and in a case that a load of a vertical component ofthe nozzle surface is applied to the head and that the carriage islocated in the first position, the guide member is configured to makecontact with the contact part of the head to receive the load applied tothe head.